Escherichia coli and Micrococcus luteus bacteria activate the CG45045 gene in the drosophila S2 cell line

The humoral immune system of Drosophila, the most studied among eukaryotes, is activated by the canonical IMD and Toll signaling pathways. Recently, new potential regulators of the innate immune response have been identified, such as long non-coding RNAs (lncRNAs) and genes encoding short polypeptides. S2 cells, being a macrophage-like cell line, are used as a model system to study the molecular mechanisms of immune response gene activation. We used this cell line to analyze the effect of Escherichia coli and Micrococcus luteus bacteria on the transcription of lncRNA-CR30055 and the CG45045 and CG44404 genes encoding short polypeptides. It was found that pathogens activate only CG45045, while the transcription levels of CR30055 and CG44404 remain unchanged. No activation of the Cecropin C gene and some Bomanin family genes was observed, indicating differences in the activation patterns of immune response genes in S2 cells and adult flies. The highest activation of CG45045 was observed between 6 and 12 hours of cell incubation with pathogens. The patterns of CG45045 activation after exposure to E. Coli and M. Luteus were similar, which may indicate common mechanisms of transcriptional activation of this gene. Thus, CG45045 may be a novel gene involved in the humoral immune response of Drosophila.